package com.chy.edu.service.impl;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.chy.edu.pojo.EduChapter;
import com.chy.edu.mapper.EduChapterMapper;
import com.chy.edu.pojo.EduVideo;
import com.chy.edu.pojo.chapter.ChapterVo;
import com.chy.edu.pojo.chapter.VideoVo;
import com.chy.edu.service.EduChapterService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.chy.edu.service.EduVideoService;
import com.chy.servicebase.exceptionhandler.GuLiException;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.ArrayList;
import java.util.List;

/**
 * <p>
 * 课程 服务实现类
 * </p>
 *
 * @author chy
 * @since 2020-10-27
 */
@Service
public class EduChapterServiceImpl extends ServiceImpl<EduChapterMapper, EduChapter> implements EduChapterService {

    @Autowired
    private EduVideoService videoService;

    // 课程大纲列表，根据课程id进行查询
    @Override
    public List<ChapterVo> getChapterVideoByCourseId(String courseId) {
        // 1. 根据课程id查询课程里面所有的章节
        QueryWrapper<EduChapter> wrapperChapter = new QueryWrapper<>();
        wrapperChapter.eq("course_id",courseId);
        List<EduChapter> eduChapterList = this.list(wrapperChapter);
        // 2. 根据课程id查询课程里面所有的小节
        QueryWrapper<EduVideo> wrapperVideo = new QueryWrapper<>();
        wrapperVideo.eq("course_id",courseId);
        List<EduVideo> eduVideoList = videoService.list(wrapperVideo);

        // 创建list集合，用于最终封装数据
        List<ChapterVo> finalList = new ArrayList<>();

        // 3. 遍历查询章节list集合进行封装
        // 遍历查询章节list集合
        for (EduChapter eduChapter : eduChapterList) {
            // eduChapter对象赋值到chapterVo里面
            ChapterVo chapterVo = new ChapterVo();
            BeanUtils.copyProperties(eduChapter,chapterVo);
            // 把chapterVo放到最终list集合
            finalList.add(chapterVo);

            // 创建集合，用于封装章节的小节
            List<VideoVo> videoList = new ArrayList<>();

            // 4. 遍历查询小节list集合进行封装
            for (EduVideo eduVideo : eduVideoList) {
                // 判断：小姐里面chapterId和章节里面id是否一样
                if (eduVideo.getChapterId().equals(eduChapter.getId())) {
                    // 进行封装
                    VideoVo videoVo = new VideoVo();
                    BeanUtils.copyProperties(eduVideo,videoVo);
                    // 放到小节封装集合
                    videoList.add(videoVo);
                }
            }

            // 把封装之后小节list集合，放到章节对象里面
            chapterVo.setChildren(videoList);
        }
        return finalList;
    }

    // 删除章节
    @Override
    public boolean deleteChapter(String chapterId) {
        // 根据chapter_id章节id 查询小节表，如果查询数据，不进行删除
        QueryWrapper<EduVideo> wrapper = new QueryWrapper<>();
        wrapper.eq("chapter_id",chapterId);
        int count = videoService.count(wrapper);
        // 判断
        if (count > 0) { // 查询出小节，不进行删除
            throw new GuLiException(20001,"不能删除");
        } else { // 不能查询数据，进行删除
            // 删除章节
            int result = baseMapper.deleteById(chapterId);
            // 成功 1 > 0
            return result > 0;
        }
    }

    // 根据课程id删除章节
    @Override
    public void removeChapterByCourseId(String courseId) {
        QueryWrapper<EduChapter> wrapper = new QueryWrapper<>();
        wrapper.eq("course_id",courseId);
        baseMapper.delete(wrapper);
    }
}
